Rick and Morty start off in the garage cleaning up multiple worm-like creatures that Rick states cannot be allowed get into the food chain. A crystal on the shelf starts to glow and Morty points out that it is the Vindicators calling to help save the universe again for what appears to be the second time. Rick outright refuses to answer an actual call to adventure, but ultimately relents because Morty brings up the fact that he gets to pick every tenth adventure.
Rick and Morty then are seen sitting at a conference table getting briefed by Supernova on the threat of Worldender. Rick ends up heckling at first then introduces every member of the Vindicators there except for Vance Maximus Renegade Star Soldier, who then shows up with everyone except for Rick seeming to idolize him. It is then revealed that this is actually the third time the Vindicators had assembled, and that they didn't invite Rick and Morty the second time due to a "personality conflict" with Rick and the rest of the Vindicators, which resulted in the deaths of three members of the Vindicators (Lady Katana, Calypso, and Diablo Verde). Rick then gets blackout drunk and we next see him pantsless and having gotten diarrhea all over the conference table. This mess is left to be cleaned up by Noob Noob instead of him going on the mission with the rest of the Vindicators. Then, Vance gives Morty a Vindicators vest as to symbolize he is a welcomed member of the Vindicators.
Inside Worldender's base, the Vindicators get through the traps left by Worldender, then get into Worldender's main room. It is then revealed that Worldender is already dying/dead and Rick then tries to leave with Morty, but then all of the Vindicators are trapped inside of the room, as set up by Rick when he was blackout drunk. Then it turns out Drunk Rick set up a Saw like sequence where people had to play games to survive or they would all die. Vance then attempts to escape only to be shot, electrocuted, buzz-sawed, and bisected in the ventilation system to his gruesome death. Morty then solves the puzzle which involved matching the Vindicators with Rick's opinions of them. In the next room Drunk Rick asks the Vindicators to locate a place they would never mention to save. Crocubot then goes to the hologram map of the universe to point out Dorian 5, however he was wrong and was killed; Dorian 5 is revealed to have been a planet destroyed (along with its populace) by the Vindicators to defeat Doom-nometron, a shape shifter located on the planet during the Vindicators 2 mission. Rick stated that if they just brought him along, he could have created a machine to located Doom-nometron in a second. Morty then goes up to the map and locates Israel on the map, which is correct, as Morty knows that when Rick is blackout drunk, he rants about Israel about defense budgets and stuff, to which Rick tries to say he isn't anti-semitic.
Then in the next room they need to make 5 three pointers in 5 minutes or else a neutrino bomb will blow up the planet. Morty goes to defuse the bomb, which is revealed to happen a lot more than Rick knew about. While that is happening, Supernova, Million Ants, and Alan Rails talk about how Supernova and Alan were previously married, and how Supernova cheated on Alan with Million Ants. Alan and Million Ants then begin to fight, Supernova then suspends them in the air and Million Ants kills Alan. In the final room, Drunk Rick asks for something he believes the Vindicators has that he wants. It is assumed Drunk Rick is talking about Morty because the Vindicators are heroes to him and Rick isn't. So Morty steps on the platform and he is taken down into a ride in which it seems Drunk Rick is expressing his love for Morty as his grandson, however it is revealed the ride was intended for Noob Noob to ride, because he laughed at Rick's jokes abut the Vindicators and Morty was caught up in hero worship. Morty then gets back out of the ride (with a look of disgust), and the platform they are on begins to rise. Supernova then goes to kill Rick and Morty for the deaths Druck Rick caused, to which Million Ants tries to convince Supernova not to do it, only for him to be killed by Supernova. Then before Supernova can try to kill Rick and Morty again, the platform reaches a party with musical star Logic singing a rap song about the Vindicators. Supernova gets away, with Rick saying that 20 people try to kill him a week, and he ends up getting high with half of them, pointing out that Gearhead is there, who then takes Morty's Vindicators vest when Morty takes it off and almost puts it on the ground, showing he doesn't like the Vindicators anymore. Beth and Summer are also at the party along with other previously seen characters; at that point Logic mentions Noob Noob in the rap song, Rick questions "Who is Noob Noob?", for Morty to show an annoyed look.
In the post-credits scene, Gearhead is seen with the Vindicators vest on trying to pick up some college girls, but then when an alien terrorist attack strikes, he then goes down an alley way, in which he ditches the vest and runs away.